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Siemens
Energy & Automation
CONFIGURATION GUIDE
CGiLL-1
Rev: 2
September 2005
Supersedes Rev 1
Ladder Logic
%RecrPmp_Stop_PB
%Close_Recirc
35
%Close_Recirc
%RecrPmp_Srt_PB
36
Gas_Start_Abort
37
Reset_MFT
Gas_OK
Start_Gas
%Start_Gas_PB
38
Gas_On
39
Start_Gas
Igniter_Proven
%Open_Gas_Valves
%Stop_Gas_PB
40
Gas_Delay
0.03333
TON
41
%Gas_V1_NotOpen
42
%Stop_Gas_PB %Gas_V2_NotOpen
Gas_Start_Abort
43
%Vent_NotClosed
44
%Open_Gas_Valves
Gas_Start_Abort
%Burner_Flame
Gas_On
45
Op_Requirements
46
ULC_Loop_Error
47
%Master_Abort_PB
%MFT
48
ULC_Loop_Error
49
%System_Alarm
CGiLL-1
CONTENTS
TABLE OF CONTENTS
SECTION AND TITLE
PAGE
1.0 INTRODUCTION ................................................................................................................................................1
2.0 CONFIGURATION OVERVIEW......................................................................................................................1
2.1 CONFIGURATION .........................................................................................................................................2
Loop Tags .......................................................................................................................................................2
Ladder Logic Pages.........................................................................................................................................2
2.2 LADDER LOGIC CONFIGURATION...........................................................................................................2
3.0 LADDER LOGIC ELEMENTS..........................................................................................................................5
3.1 LADDER ELEMENTS...................................................................................................................................5
Power Rail (PR) |............................................................................................................................................5
Horizontal Shunt (HS) -----.............................................................................................................................5
Vertical Shunt (VS) | .......................................................................................................................................5
Connections By Reference <reference>..........................................................................................................5
3.2 CONTACTS.....................................................................................................................................................6
Normally Open Contact --| |-- NOC ................................................................................................................6
Normally Closed Contact --|\|-- NCC..............................................................................................................6
Positive Transition Sensing Contact --|P|-- PTC .............................................................................................6
Negative Transition Sensing Contact --|N|-- NTC ..........................................................................................6
3.3 COILS ..............................................................................................................................................................7
Coil --(C)-- ......................................................................................................................................................7
Set (Latch) Coil --(S)--....................................................................................................................................7
Reset (Unlatch) Coil --(R)-- ............................................................................................................................7
Retentive (Memory) Coil --(M)--....................................................................................................................7
Set Retentive (Memory) Coil --(SM)-- ...........................................................................................................7
Reset Retentive (Memory) Coil --(RM)-- .......................................................................................................8
Positive Transition-Sensing Coil --(P)-- .........................................................................................................8
Negative Transition-Sensing Coil --(N)-- .......................................................................................................8
Negated Coil --(NG)--.....................................................................................................................................8
3.4 TIMERS ...........................................................................................................................................................9
Retentive On Timer --(ROT)-- ........................................................................................................................9
Enable Retentive On Timer --(EROT)-- .........................................................................................................9
Retentive On Timer (Memory) --(ROTM)-- ...................................................................................................9
Enable Retentive On Timer (Memory) --(EROTM)--.....................................................................................9
On-Delay Timer --(TON)-- ...........................................................................................................................10
On-Delay Retentive (Memory) Timer --(TONM)-- ......................................................................................10
Off-Delay Timer --(TOF)-- ...........................................................................................................................10
Off-Delay Retentive (Memory) Timer --(TOFM)-- ......................................................................................10
Timed Pulse Timer --(TP)-- ..........................................................................................................................11
Timed Pulse Retentive (Memory) Timer --(TPM)-- .....................................................................................11
Retriggerable Timed Pulse Timer --(RTP)-- .................................................................................................11
Retriggerable Timed Pulse Retentive (Memory) Timer --(RTPM)-- ............................................................11
Repeat Cycle Timer --(RCT)-- ......................................................................................................................12
Repeat Cycle Retentive (Memory) Timer --(RCTM)-- .................................................................................12
4.0 LADDER LOGIC DESIGN EXAMPLE..........................................................................................................13
September 2005
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CONTENTS
CGiLL-1
Changes for Rev 2, September 2005
•
There were no technical changes.
•
References to Moore Products, Co. were replaced with Siemens Energy & Automation, Inc.
•
Disclaimer text updated.
•
Add Product Support section.
Procidia, i|config, and i|station are trademarks of Siemens Energy & Automation, Inc. Other trademarks are the property of
their respective owners. All product designations may be trademarks or product names of Siemens Energy & Automation, Inc. or
other supplier companies whose use by third parties for their own purposes could violate the rights of the owners.
Siemens Energy & Automation, Inc. assumes no liability for errors or omissions in this document or for the application and use
of information in this document. The information herein is subject to change without notice.
Procedures in this document have been reviewed for compliance with applicable approval agency requirements and are
considered sound practice. Neither Siemens Energy & Automation, Inc. nor these agencies are responsible for repairs made by
the user.
Copyright © 2005, Siemens Energy & Automation, Inc.
ii
September 2005
CGiLL-1
INTRODUCTION AND OVERVIEW
1.0 INTRODUCTION
This Configuration Guide provides detailed descriptions of Procidia™ ladder logic elements and their
implementation.
The Procidia Internet Control System (ICS), the Model 353 Process Automation Controller, and the Model 354N
Universal Loop Controller represent the next generation in controller technology. Designed to satisfy the needs of
both continuous and discrete control applications, these controllers have access to a large library of reusable
function blocks that can be applied to a configuration to manage a vast array of process control applications.
Depending upon controller model, either a Universal Serial Bus or a LonWorks® fieldbus interface extends the
analog and digital I/O of these controllers over a low cost, easy to install twisted pair cable. As a result, applications
traditionally requiring a single-loop controller and a PLC can now be accomplished in a single controller.
Ladder logic configurations are built using the i|config™ Graphical Configuration Software. Install the software on
a Windows®-based personal computer or on an i|station™ Industrial PC. When completed, the configuration is then
downloaded to the target controller.
Related Literature
This manual can be used with:
•
i|config Graphical Configuration Utility Software Guide SG15939-64 - This manual describes use of the
software to create and download a configuration.
•
Procidia Function Blocks and FCOs Configuration Guide CGiFB-1 - This manual contains a description of
each function block and factory configured option provided in controller firmware.
•
Procidia i|pac™ User’s Manual UMiPAC-1 (and -2) - This manual describes installation of the i|pac and i|o™
hardware and UMiPAC-1 contains CGiFB-1.
•
Controller User’s Manuals UM353-1 and UM354N-1 - Each manual describes installation of the named
controller and it contains the function block and factory configured option details for that controller.
Product Support
Telephone
NORTH AMERICA
Fax
E-mail
Hours of Operation
Public Internet Site
Repair Service
+1 800 569 2132, option 2 for Siemens-Moore brand
instruments
+1 215 646 3547
[email protected]
8 a.m. to 4:45 p.m. eastern time
Monday – Friday (except holidays)
www.sea.siemens.com/ia/
+1 215 646 7400 extension 3187
For contact information outside North America, visit the Siemens public Internet site (see the above table for the
URL), locate “Customer Support Process Instrumentation,” and click on the Contact Tech Support link to access the
Global Support link.
2.0 CONFIGURATION OVERVIEW
Controller configuration is the selecting and interconnecting of function blocks from an available list and the
entering of appropriate block parameters to implement a specific control strategy. Although configuration affects
the entire controller, the controller partitions related control implementations into LOOPS.
Each LOOP can contain the function blocks listed in the above manuals. Signals can be connected between
function blocks within the LOOP as well as between loops. Also, there are several STATION function blocks that
are fixed and available in the STATION menu for setting station related values, such as security. Ladder logic
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INTRODUCTION AND OVERVIEW
CGiLL-1
status can be displayed using the Operator Display for Discrete Indications and Control (ODD) function block and a
logic sequence can be initiated from an Operator Display for PushButtons (ODP) function block. Refer to CGiFB-1
or the controller’s User’s Manual for the list of function blocks and their definitions.
Each controller must be configured to perform the desired control strategy. The arrangement of functions and the
numerical data required for a particular control circuit are referred to as the controller configuration.
A configuration is designed by first arranging the needed function blocks in a fashion similar to that of a P & ID
drawing. Parameter and calibration values are determined next and then entered on a Configuration Documentation
Form (e.g., CG353-2) and finally into the Graphical Configuration software.
2.1 CONFIGURATION
This section provides tips for use while configuring a controller. Most references to controller displays are to those
seen on either i|station or a Local Faceplate, Display Assembly faceplate, or Faceplate Display, depending upon
controller model.
Loop Tags
Begin a configuration by laying down all of the loops and assigning loop tag names. A loop tag should be a
meaningful name of 6 to 8 characters, although a tag name can be up to 12 characters. The controller will display 8
characters: the last 6 characters in the tag name, a period, and a variable (P, S, V, X, Y, T or “ ”). The entire tag
name, when more than 6 characters, can be viewed by pressing the TAG key. For example, a tag of “Primary” is
displayed as “rimary.P”. The “.P” indicates that the process variable is shown in the digital display. When the Tag
key is pressed, the full tag would scroll “Primary”.
To avoid scrolling and show the tag name and variable, condense the tag name. For example, condensing
“Primary” to “Prim” would cause the display to read “Prim.P”.
A ladder logic loop tag name should be up to 8 characters. While in configuration mode, a maximum of 8
characters can be displayed.
The controller distinguishes between analog and digital signals. If you need to convert a digital signal to analog,
use the Transfer Switch block (TSW). The inputs do not need to be configured. If you need to convert an analog
signal into digital, use a Comparator block (CMP) 1.
When creating a large loop configuration, first go into Page view and then lay down all the blocks. This will permit
you to quickly organize the blocks in a logical order.
Ladder Logic Pages
Up to four pages of ladder logic rungs are permitted in the ladder logic loops. In practice, it is best to use only two
pages of ladder logic per loop. After the second page, you typically will run out of loop resources. For this reason,
it is best to switch to a new loop after two pages of ladder.
When configuring ladder logic, it is useful to skip a rung between each rung of ladder created. While debugging the
ladder logic, you will probably need to add more contacts or rungs of logic. Having unused rungs makes it easy to
add needed rungs.
2.2 LADDER LOGIC CONFIGURATION
A summary of the steps involved in assigning names to Ladder Logic elements follows. Each step is then further
divided into steps is subsequent paragraphs.
1.
Create the loops necessary for the ladder.
2.
Enter the discrete inputs to the ladder in the Reference list.
1
For function block details, refer to CGiFB-1, UMiPAC-1, UM353-1, or UM354N-1.
2
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CGiLL-1
3.
Draw the ladder.
4.
Name the contacts in the ladder.
5.
Name the coils in the ladder.
6.
Connect the coils to the discrete outputs.
INTRODUCTION AND OVERVIEW
Create the loops necessary for the ladder
1.
Create a function block loop called “Disc I/O”.
2.
In this loop, place all of the I/O blocks that will be used by the ladder, such as DIN's, DID's, DOUT's and DOD
blocks.
3.
Create a ladder logic loop to construct the ladder.
Create the Reference List for the discrete inputs to the ladder
1.
Select Reference from the Edit>References menu to get the Edit/Reference dialog box.
2.
Left click on the Create button to get the Create/Modify References dialog box.
3.
Type in the reference name of the discrete inputs to the ladder, such as “FAN RUNNING” or “FLAME ON”.
4.
Now click on the check mark in the box next to ‘Unconfigured’ to configure the input. (Alternatively, click on
the name of the loop containing the Discrete I/O in the ladder.) It is now possible to select the loop, block, and
output that will be connected to the discrete input.
A % symbol will appear in front of the reference name. This indicates that the reference is connected from the
ladder to a signal outside the station. A > symbol indicates a connection from the ladder to another loop within the
station. No symbol in front of the reference name indicates that it is connected within the ladder only.
Draw the ladder
1.
Draw the ladder by selecting the New Ladder Logic Element button from the Line Connection Toolbar and
selecting the appropriate contacts and coils.
2.
Next, select the Line Connection Mode button on the Line Connection Toolbar. The cursor will change to a
wire spool that is used to interconnect or "wire" the elements in the ladder.
3.
Wire all the elements into the desired ladder logic configuration.
Name the contacts on the ladder
1.
Name the contacts in the ladder using the wire spool cursor. Right click on the contact name. The set reference
dialog box will pop up.
2.
For external inputs, select the proper discrete input from the list created earlier.
3.
Add to the reference list any contact that comes from a loop within the station. Select the Edit/References
button and click on the Create button. The Create/Modify References dialog box will pop up. Name the
contact reference and then specify the loop block and output used to provide this discrete input to the ladder.
4.
If a contact comes from a coil on the ladder, leave it unconfigured until the coils are named in the next step.
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INTRODUCTION AND OVERVIEW
CGiLL-1
Name the coils on the ladder
1.
To name coils, continue to use the wire spool. Right click on the coil name; usually it will be in the form of
DefCoilTagn.
2.
The Create/Modify Reference dialog box will pop up with the coil name highlighted.
3.
Change the reference name to the appropriate name and click on OK.
4.
Go to the next coil and repeat this procedure until all the coils are named.
5.
Go back through the ladder and name the unconfigured contacts that come from the coils that were just named.
This is done by using the wire spool and right clicking ‘Unconfigured’ above the contact. As before, the Set
Reference dialog box pops up and the appropriate coil name may be selected from the references listed by
highlighting the appropriate name and clicking on OK.
Connect coils to discrete outputs
1.
Connect each coil that drives a discrete output, such as START FAN, OPEN GAS SSV's, to a discrete output
block. This is accomplished by opening the "Discrete I/O" function block loop with the Line Connection
Selected Mode cursor button that is next the wire spool button.
2.
Double click on the appropriate discrete block. The Item Attributes dialog box will pop up.
3.
Click on the tab for the block selected.
4.
Then click on the appropriate input to highlight it.
5.
Next, highlight the word Reference in the Connect to box.
6.
Then click on the Edit Input button in that box. The Set Reference list will pop up with all the coil names
listed.
7.
Click on the proper coil name that corresponds to the discrete output channel desired and then click OK. This
connects the coil to that discrete output channel. When the coil goes high, the discrete output will go high.
4
September 2005
CGiLL-1
LADDER LOGIC ELEMENTS
3.0 LADDER LOGIC ELEMENTS
Logic functions are implemented in a controller using function blocks (Boolean functions). Many users, however,
prefer ladder diagrams for developing logic configurations. The graphical configuration utility can be used to
configure logic using ladder techniques. This section provides a list of ladder diagram elements, contacts, coils, and
timers available for use within the graphical configuration utility. It also describes how they correspond to controller
function blocks. A sample ladder logic page with a variety of elements is shown below.
%RecrPmp_Stop_PB
%Close_Recirc
35
%Close_Recirc
%RecrPmp_Srt_PB
36
Gas_Start_Abort
37
Reset_MFT
Gas_OK
Start_Gas
%Start_Gas_PB
38
Gas_On
39
Start_Gas
Igniter_Proven
%Open_Gas_Valves
%Stop_Gas_PB
40
Gas_Delay
0.03333
TON
41
%Gas_V1_NotOpen
42
%Stop_Gas_PB %Gas_V2_NotOpen
Gas_Start_Abort
43
%Vent_NotClosed
44
%Open_Gas_Valves
Gas_Start_Abort
%Burner_Flame
Gas_On
45
Op_Requirements
46
ULC_Loop_Error
47
%Master_Abort_PB
%MFT
48
ULC_Loop_Error
%System_Alarm
49
3.1 LADDER ELEMENTS
Power Rail (PR) |
This element is on the left of the ladder diagram and is always conducting.
Horizontal Shunt (HS) ----This element conducts when the element on the left is conducting and transfers this state to the element on the right.
Vertical Shunt (VS) |
This element is the inclusive OR of the states of the elements to its left.
Connections By Reference <reference>
The <reference> is the connection element to other elements within the ladder diagram and to inputs and outputs of
function blocks within the loop.
September 2005
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LADDER LOGIC ELEMENTS
CGiLL-1
3.2 CONTACTS
A contact is a ladder element that copies a state to the element on its right equal to the logical AND of the state of
the element on its left with the state of the reference.
Normally Open Contact --| |-- NOC
The NOC copies the state of the left horizontal shunt to the right
<reference>
A
horizontal shunt, if the state of the contact reference is TRUE.
A
ANDxx O1
B
O1
B
Otherwise the state of the right horizontal shunt will be nonNOC
conducting. {The NOC is equivalent to a two input AND function
block having inputs A <reference> & B and output O1. If the B
input is connected to the Power Rail the contact output will equal the <reference> and an actual AND function
block is not required.}
Normally Closed Contact --|\|-- NCC
The NCC copies the state of the left horizontal shunt to the right
<reference>
horizontal shunt, if the state of the contact reference is FALSE.
O1
A
A
A
NOTxx
B
O1
ANDxx O1
B
Otherwise the state of the right horizontal shunt will be nonNCC
conducting. {The NCC is equivalent to a two input AND function
block having inputs A <reference> & B and output O1 and a NOT
function connected to the A input of the AND block.. If the B input is connected to the Power Rail the contact output
will equal the output of the NOT function block and an AND function block is not required. }
Positive Transition Sensing Contact --|P|-- PTC
The PTC copies the state of the left horizontal shunt to the right
<reference>
A
horizontal shunt for one scan cycle, when the state of the contact
O1
A
A
O1
B
RTGxx
P
ANDxx O1
B
reference changes from FALSE to TRUE. Otherwise the state of
PTC
the right horizontal shunt will be non-conducting. {The PTC
function is equivalent to a two input AND function block having
inputs A <reference> & B and output O1 and a RTG rising edge trigger function connected to the A input. If the B
input is connected to the Power Rail the contact output will equal the output of the RTG function block and an AND
function block is not required.}
Negative Transition Sensing Contact --|N|-- NTC
The NTC copies the state of the left horizontal shunt to the right
<reference>
horizontal shunt for one scan cycle, when the state of the contact
A
O1
A
A
O1
B
FTGxx
ANDxx O1
N
B
reference changes from TRUE to FALSE. Otherwise the state of
NTC
the right horizontal shunt will be non-conducting. {The NTC
function is equivalent to a two input AND function block having
inputs A <reference> & B and output O1 and a FTG falling edge trigger function connected to the A input. If the B
input is connected to the Power Rail the contact output will equal the output of the FTG function block and an AND
function block is not required.}
6
September 2005
CGiLL-1
LADDER LOGIC ELEMENTS
3.3 COILS
Coils copy the state of the left horizontal shunt to the right horizontal shunt without modification and store the state
of the left horizontal shunt into a Boolean variable, having a unique user assigned name for use within the graphical
ladder diagram.
Coil --(C)-The C coil sets the state of the reference to TRUE when the left
horizontal shunt is conducting and to FALSE when not conducting.
{The coil function is associated with the output state of another
function block and assigns a unique reference name within the
ladder diagram to this state.}
<REFERENCE>
O1
O1
C
Set (Latch) Coil --(S)-The S coil sets the state of the coil reference TRUE when the left
S
<reference>
S
horizontal shunt changes from not conducting to conducting. It will
O1
O1
R
SRFxx
S
S
remain TRUE, after the left horizontal shunt returns to a not
S
PU LAST = NO
conducting state, until the reference is reset using an R coil assigned
to the same reference. During a warm or cold start the reference will
be set to FALSE. {The set coil function is equivalent to a SRF function block having input S connected to the left
horizontal shunt, the block output O1 associated with the coil reference, and PU LAST set to NO. The left horizontal
shunt of the corresponding R coil is connected to the R input. Set is paired with the complementary Reset function. }
Reset (Unlatch) Coil --(R)-The R coil resets the state of the coil reference to FALSE when the
S
O1
<reference>
R
SRFxx
left horizontal shunt changes from not conducting to conducting. It
O1
R
R
R
will remain FALSE after the left horizontal shunt returns to a not
R
PU LAST = NO
conducting state, until the reference is set using an S coil assigned to
the same reference. During a warm or cold start the reference will
be set to FALSE. {The reset coil function is equivalent to a SRF function block having input R connected to the left
horizontal shunt, the block output O1 associated with the coil reference, and PU LAST set to NO. The left
horizontal shunt of the corresponding S coil is connected to the S input. Reset is paired with the complementary Set
function. }
Retentive (Memory) Coil --(M)-The M coil sets the state of the coil reference to TRUE when the left
S
<reference>
S
horizontal shunt is conducting and will set it to FALSE when the
O1
SRFxx O1
S
S
shunt is not conducting. It will retain the state of the reference
M
PU LAST = YES
during a warm start until the coil is executed on the first scan cycle.
{The retentive coil function is equivalent to a SRF function block
having input S connected to the left horizontal shunt, the R input is not connected (defaulting to TRUE), the block
output O1 associated with the coil reference, and PU LAST set to YES. }
Set Retentive (Memory) Coil --(SM)-The SM coil sets the state of the coil reference TRUE when the left
S
<reference>
S
horizontal shunt changes from not conducting to conducting. It will
O1
O1
R
SRFxx
S
S
remain TRUE, after the left horizontal shunt returns to a not
SM
PU LAST = YES
conducting state, until the reference is reset using a RM coil assigned
to the same reference. During a warm start the reference will be
retained at the previous value and during a cold start it will be set to FALSE. {The set retentive coil function is
equivalent to a SRF function block having input S connected to the left horizontal shunt, the block output O1
associated with the coil reference, and PU LAST set to YES. The left horizontal shunt of the corresponding RM coil
is connected to the R input. Set is paired with the complementary Reset function below. }
September 2005
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LADDER LOGIC ELEMENTS
CGiLL-1
Reset Retentive (Memory) Coil --(RM)-The RM coil resets the state of the coil reference to FALSE when
S
O1
<reference>
R
the left horizontal shunt changes from not conducting to conducting.
SRFxx
O1
R
R
R
It will remain FALSE after the left horizontal shunt returns to a not
RM
PU LAST = YES
conducting state, until the reference is set using a SM coil assigned
to the same reference. During a warm start the reference will be
retained at the previous value and during a cold start it will be set to FALSE. {The reset retentive coil function is
equivalent to a SRF function block having input R connected to the left horizontal shunt, the block output O1
associated with the coil reference, and PU LAST set to YES. The left horizontal shunt of the corresponding SM coil
is connected to the S input. Reset is paired with the complementary Set function above. }
Positive Transition-Sensing Coil --(P)-The P coil changes the state of the coil reference from FALSE to
TRUE for one scan cycle, when the left horizontal shunt changes
from not conducting to conducting. {The positive transition-sensing
coil function is equivalent to a RTG function block having input A
connected to the left horizontal shunt and the block output O1
associated with the coil reference. }
<reference>
O1
A
A
RTGxx
A
O1
A
P
Negative Transition-Sensing Coil --(N)-The N coil changes the state of the coil reference from FALSE to
TRUE for one scan cycle, when the left horizontal shunt changes
from conducting to not conducting. {The negative transition-sensing
coil function is equivalent to a FTG function block having input A
connected to the left horizontal shunt and the block output O1
associated with the coil reference. }
<reference>
A
O1
A
A
O1
FTGxx
A
N
Negated Coil --(NG)-The NG coil sets the state of the coil reference TRUE when the left
horizontal shunt not conducting and to FALSE when conducting.
{The negated coil function is equivalent to a NOT function block
having input A connected to the left horizontal shunt and the block
output O1 associated with the coil reference. }
8
<reference>
A
NG
O1
A
O1
A
NOTxx
A
September 2005
CGiLL-1
LADDER LOGIC ELEMENTS
3.4 TIMERS
Timers are similar to coils. They copy the state of the left horizontal shunt to the right horizontal shunt without
modification and store a state into a Boolean reference based on the state of the left horizontal shunt and the
operation of the specific timer function.
Retentive On Timer --(ROT)-The ROT changes its coil reference from FALSE to TRUE after the
ON
<reference>
left horizontal shunt has been conducting for a time equal to or
D
ON
D
ON
ON
greater than the time setting, provided its associated EROT is
ROTxx ND
ROT
conducting. Once the timer has been started, the elapsed time will
EN
ET
TIME <time>
EN
ET (elapsed time)
be retained even if the left horizontal shunt returns to a not
conducting state. The elapsed timer will continue when the state
NOT<reference>
returns to conducting. The ROT must be used with an EROT
ND
PU LAST = NO
EN
EN
(enable retentive on timer) having the same reference as the ROT
DLY TIME = TIME <time>
EROT
but preceded by NOT (e.g. ROT is TIMER1 and EROT is
NOTTIMER1). During a warm or cold start the reference will be
initialized to FALSE and the elapsed timer will be initialized to 0. {This function and its associated EROT
corresponds to a ROT function block with the PU LAST set to NO, the left horizontal shunt connected to the ON
input, and the D output corresponding to the reference. The left horizontal shunt of the corresponding EROT coil is
connected to the EN input. }
Enable Retentive On Timer --(EROT)-The EROT changes its coil reference from FALSE to TRUE when the left horizontal shunt is conducting and its
associated ROT is NOT TRUE. {This function and its associated ROT corresponds to a ROT function block with
the PU LAST set to NO, the left horizontal shunt connected to the EN input, and the DN output corresponding to the
reference. The left horizontal shunt of the corresponding ROT coil is connected to the ON input. }
Retentive On Timer (Memory) --(ROTM)-The ROTM changes its coil reference from FALSE to TRUE after
<reference>
ON
D
the left horizontal shunt has been conducting for a time equal to or
D
ON
ON
ON
greater than the time setting, provided its associated EROTM is
ND
ROTM
ROTxx
EN
ET
conducting. Once the timer has been started, the elapsed time will
TIME <time>
ET (elapsed time)
EN
be retained even if the left horizontal shunt returns to a not
conducting state. The elapsed timer will continue when the state
NOT<reference>
returns to conducting. The ROTM must be used with an EROTM
ND
PU LAST = YES
EN
EN
DLY TIME = TIME <time>
(enable retentive on timer) having the same reference as the ROTM
EROTM
but preceded by NOT (e.g. ROTM is TIMER2 and EROTM is
NOTTIMER2). During a warm start the references and elapsed
timer will be initialized to their previous values. {This function and the matching EROTM corresponds to a ROT
function block with the PU LAST set to YES, the left horizontal shunt connected to the ON input, and the D output
corresponding to the reference. The left horizontal shunt of the associated EROTM coil is connected to the EN
input. }
Enable Retentive On Timer (Memory) --(EROTM)-The EROTM changes its coil reference from FALSE to TRUE when the left horizontal shunt is conducting and its
associated ROTM is NOT TRUE. {This function and its associated ROTM corresponds to a ROT function block
with the PU LAST set to YES, the left horizontal shunt connected to the EN input, and the DN output corresponding
to the reference. The left horizontal shunt of the associated ROTM coil is connected to the ON input. }
September 2005
9
LADDER LOGIC ELEMENTS
CGiLL-1
On-Delay Timer --(TON)-The TON changes the coil reference from FALSE to TRUE after the
P
<reference>
left horizontal shunt changes from not conducting to conducting and
P
O1
O1
P
P
DYTxx ET
has been conducting for a time equal to or greater than the time
TON
setting. The reference will remain TRUE until the left horizontal
TIME <time>
TYPE = ON
ET (elapsed time)
PU LAST = NO
shunt returns to a not conducting state. During a warm start the
DYT TIME = TIME <time>
reference will be set FALSE, any elapsed time will reset to 0.0, and
the timer will act on state of the left horizontal shunt during the first
scan. {The TON function is equivalent to the DYT function block with the TYPE set to ON, PU LAST set to NO, and
the DLY TIME set to the time.}
On-Delay Retentive (Memory) Timer --(TONM)-The TONM changes the coil reference from FALSE to TRUE after
P
<reference>
the left horizontal shunt changes from not conducting to conducting
O1
P
O1
P
P
DYTxx ET
and has been conducting for a time equal to or greater than the time
TONM
setting. It will remain TRUE until the left horizontal shunt returns to
TIME <time>
TYPE = ON
ET (elapsed time)
PU LAST = YES
a not conducting state. During a warm start the reference will be set
DYT TIME = TIME <time>
to the last state, any elapsed time will be retained including that time
accumulated during a power out condition. The timer will act on the
state of the left horizontal shunt during the first scan based on the state of the last scan prior to power out. {The
TONM function is equivalent to the DYT function block with the TYPE set to ON, PU LAST set to YES, and the DLY
TIME set to the time.}
Off-Delay Timer --(TOF)-The TOF changes the coil reference from TRUE to FALSE after the
P
<reference>
left horizontal shunt changes from conducting to not conducting and
P
O1
O1
P
P
DYTxx ET
has been in a not conducting state for a time equal to or greater than
TOF
the time setting. It will remain FALSE until the left horizontal shunt
TIME <time>
TYPE = OFF
ET (elapsed time)
PU LAST = NO
returns to a conducting state. During a warm start the reference will
DYT TIME = TIME <time>
be set FALSE, any elapsed time will reset to 0.0, and the timer will
act on state of the left horizontal shunt during the first scan. {The TOF
function is equivalent to the DYT function block with the TYPE set to OFF, PU LAST set to NO, and the DLY TIME
set to the time.}
Off-Delay Retentive (Memory) Timer --(TOFM)-The TOFM changes the coil reference from TRUE to FALSE after the
P
<reference>
left horizontal shunt changes from conducting to not conducting and
P
O1
O1
P
P
DYTxx ET
has been in a not conducting state for a time equal to or greater than
TOFM
the time setting. It will remain FALSE until the left horizontal shunt
TIME <time>
TYPE = OFF
ET (elapsed time)
PU LAST = YES
returns to a conducting state. During a warm start the reference will
DYT TIME = TIME <time>
be set to the last value, the elapsed time will be retained, including
any time accumulated during a power out condition, and the timer will
act on the state of the left horizontal shunt during the first scan based on the state on the last scan prior to power out.
{The TOF function is equivalent to the DYT function block with the TYPE set to OFF, PU LAST set to YES, and the
DLY TIME set to the time.}
10
September 2005
CGiLL-1
LADDER LOGIC ELEMENTS
Timed Pulse Timer --(TP)-The TP changes the coil reference from FALSE to TRUE when the
P
<reference>
left horizontal shunt changes from a not conducting to a conducting
P
O1
O1
P
P
state and will remain TRUE for a period equal to the time setting
OSTxx ET
TP
regardless of the state of the left horizontal shunt. The timed pulse
TIME <time>
RETRIG = NO
can not be retriggered until after the time expires. During a warm
PU LAST = NO
ET (elapsed time)
ON TIME = TIME <time>
start the reference will be set FALSE, any elapsed time will reset to
0.0, and the timer will act on state of the left horizontal shunt during
the first scan. {The TP function is equivalent to the OST function block with RETRIG set to NO, PU LAST set to NO,
and the ON TIME set to the time.}
Timed Pulse Retentive (Memory) Timer --(TPM)-The TPM changes the coil reference from FALSE to TRUE when the
P
<reference>
left horizontal shunt changes from a not conducting to a conducting
O1
P
O1
P
P
OSTxx ET
state and will remain TRUE for a period equal to the time setting
TPM
regardless of the state of the left horizontal shunt. The timed pulse
TIME <time>
RETRIG = NO
PU LAST = YES
can not be retriggered until after the time expires. During a warm
ET (elapsed time)
ON TIME = TIME <time>
start the reference will be set to the last state, any elapsed time will be
retained including that time accumulated during a power out condition, the timer will continue timing, if time has
not elapsed, and if elapsed will act on state of the left horizontal shunt during the first scan based on the state during
the last scan prior to power out. {The TP function is equivalent to the OST function block with RETRIG set to NO,
PU LAST set to YES, and the ON TIME set to the time.}
Retriggerable Timed Pulse Timer --(RTP)-The RTP changes the coil reference from FALSE to TRUE when the
P
<reference>
left horizontal shunt changes from a not conducting to a conducting
O1
P
O1
P
P
OSTxx ET
state and will remain TRUE for a period equal to the time setting
RTP
regardless of the state of the left horizontal shunt. The timed pulse can
TIME <time>
RETRIG = YES
PU LAST = NO
be retriggered if the left horizontal shunt changes from a not
ET (elapsed time)
ON TIME = TIME <time>
conducting to a conducting state during the timing period. During a
warm start the reference will be set FALSE, any elapsed time will reset to 0.0, and the timer will act on the state of
the left horizontal shunt during the first scan. {The TP function is equivalent to the OST function block with RETRIG
set to YES, PU LAST set to NO, and the ON TIME set to the time.}
Retriggerable Timed Pulse Retentive (Memory) Timer --(RTPM)-The RTPM changes the coil reference from FALSE to TRUE when
P
<reference>
the left horizontal shunt changes from a not conducting to a
O1
P
O1
P
P
conducting state and will remain TRUE for a period equal to the
OSTxx ET
RTPM
time setting regardless of the state of the left horizontal shunt. The
TIME <time>
RETRIG = YES
timed pulse can be retriggered if the left horizontal shunt changes
PU LAST = YES
ET (elapsed time)
from a not conducting to a conducting state during the timing
ON TIME = TIME <time>
period. During a warm start the reference will be set to the last
state, any elapsed time will retained including that time accumulated during a power out condition, the timer will
continue timing if time has not elapsed, and if elapsed will act on state of the left horizontal shunt during the first
scan based on the state during the last scan prior to power out. {The TP function is equivalent to the OST function
block with RETRIG set to NO, PU LAST set to YES, and the ON TIME set to the time.}
September 2005
11
LADDER LOGIC ELEMENTS
CGiLL-1
Repeat Cycle Timer --(RCT)-The RCT changes the coil reference from FALSE to TRUE when
S
the left horizontal shunt changes from a not conducting to a
<reference>
S
O1
O1
conducting state and will remain TRUE for a period equal to the on
S
S
RCTxx ET
RCT
time. At the end of the on time the reference will go FALSE and
ON <time>
PU LAST = NO
remain FALSE until the off time expires. It will continue to repeat
OFF <time>
ON TIME = ON <time>
this cycle as long as the left horizontal shunt is conducting. The
ET (elapsed time)
OFF TIME = OFF <time>
reference will always be FALSE when the left horizontal shunt is
not conducting. During a warm start the reference will be set
FALSE, any elapsed time will reset to 0.0, and the timer will act on state of the left horizontal shunt during the first
scan. {The RCT function is equivalent to the RCT function block with INPUT AT unconfigured, PU LAST set to NO,
the ON TIME set to the on time, and the OFF TIME set to the off time.}
Repeat Cycle Retentive (Memory) Timer --(RCTM)-The repeat cycle retentive timer RCTM changes the coil reference
S
<reference>
S
O1
from FALSE to TRUE when the left horizontal shunt changes from
O1
S
S
RCTxx ET
a not conducting to a conducting state and will remain TRUE for a
RCTM
period equal to the on time. At the end of the on time the reference
ON <time>
PU LAST = YES
OFF <time>
ON TIME = ON <time>
will go FALSE and remain FALSE until the off time expires. It will
ET (elapsed time)
OFF TIME = OFF <time>
continue to repeat this cycle as long as the left horizontal shunt is
conducting. The reference will always be FALSE when the left
horizontal shunt is not conducting. During a warm start the reference will be set to the last value, any elapsed time
will retained including that time accumulated during a power out condition, and the timer will act on state of the left
horizontal shunt during the first scan. {The RCT function is equivalent to the RCT function block with INPUT AT
unconfigured, PU LAST set to YES, the ON TIME set to the on time, and the OFF TIME set to the off time.}
12
September 2005
CGiLL-1
LADDER LOGIC DESIGN EXAMPLE
4.0 LADDER LOGIC DESIGN EXAMPLE
This section illustrates a typical controller ladder logic configuration using the graphical configuration utility. The
configuration consists of a function block loop and a ladder logic loop. The function block loop contains the
discrete I/O function blocks required to process the physical inputs and outputs to the station. The ladder logic loop
contains the ladder logic diagrams.
O0
DID01
O0
0
O1
1
O2
O2
2
O3
O3
3
O4
O4
4
O1
DID02
O5
O5
5
O6
O6
6
O7
O7
7
O8
O8
8
O9
O9
DOD01
OA
A
OB
OB
B
OC
OC
C
OD
OD
D
OE
OE
E
OF
OF
F
QS
QS
RN
ODS
01
LE
02
03
04
9
OA
SN
05
CN
06
CM
07
L
08
NL
09
WD
Reference connections for function block DID01:
Output O0:
Output O1:
Output O2:
Output O3:
Output O4:
Output O5:
Output O6:
Output O7:
September 2005
%FDF_Start_PB
%FDF_Stop_PB
%FD_Fan_Running
%Air_Flow_LoLo
%Drum_Level_LoLo
%Oil_Temp_Lo
%Oil_HdrPress_Lo
%Atom_Med_Hi
Output O8:
Output O9:
Output OA:
Output OB:
Output OC:
Output OD:
Output OE:
Output OF:
%Gas_Press_Lo
%Gas_Press_Hi
%Gas_V1_Closed
%Gas_V2_Closed
%Oil_V1_Closed
%Oil_V2_Closed
%Start_Purge_PB
%Reset_MFT_PB
13
LADDER LOGIC DESIGN EXAMPLE
CGiLL-1
Reference connections for function block DID02:
Output O0:
Output O1:
Output O2:
Output O3:
Output O4:
Output O5:
Output O6:
Output O7:
%Start_Ignitr_PB
%Burner_Flame
%Start_Oil_PB
%Stop_Oil_PB
%Oil_V1_NotOpen
%Oil_V2_NotOpen
%RecircPmp_Stop_PB
%RecircPmp_Strt_PB
Output O8:
Output O9:
Output OA:
Output OB:
Output OC:
Output OD:
Output OE:
Output OF:
%Start_Gas_PB
%Stop_Gas_PB
%Gas_V1_NotOpen
%Gas_V2_NotOpen
%Vent_NotClosed
%Master_Abort_PB
%
%
Reference connections for function block DOD01:
Input 0:
Input 1:
Input 2:
Input 3:
Input 4:
Input 5:
Input 6:
Input 7:
%FDF_Start
%Start_Purge
%Purge_InProgress
%Purge_Complete
%Opn_Ig_Gas_Vlvs
%Open_Oil_Valves
%Close_Recirc
%Open_Gas_Valves
Input 8: %MFT
Input 9: %System_Alarm
Input A: %
Input B: %
Input C: %
Input D: %
Input E: %
Input F: %
Reference connections for function block ODS:
Output LE:
Model 353_Loop_Error
The ODS can be used for displaying various operations within the ladder logic loops. The Universal display
provides more capability for this type of loop in that it will be able to display various messages. See the description
of the ODS function block for additional information. When a basic display is used it will normally display the loop
tag.S and indicate the step number of the sequencer, if used. If message inputs are configured and a basic display is
used they can be viewed by pressing the D button to advance through the list of active messages.
Other function blocks can also be used to provide boolean inputs or outputs to the ladder logic elements. For
example, a pushbutton function block could be used to start or stop a logic operation. The connections between
these elements on the primary page are made by creating a reference for the inputs and outputs of these function
blocks, similar to that above for the discrete I/O.
14
September 2005
CGiLL-1
LADDER LOGIC DESIGN EXAMPLES
The graphical configuration of the first secondary page:
%FDF Start
1
%FDF Start PB
%FDF Stop PB
%FDF_Start
2
%FDF Fan Running %Air Flow LoLo
%Drum Level LoLo
Boiler_OK
3
%Oil Temp Lo
%Oil HdrPress Lo
%Gas Press Lo
%Gas Press Hi
Boiler OK
Oil OK
%Atom Med Hi
Oil_OK
4
Gas_OK
5
Gas OK
Op_Requirements
6
%Gas V1Closed
%Gas V2 Closed
Op Requirements
Purge Precond
%Oil V1 Closed
%Oil V2 Closed
Purge_Precond
7
Purge_Permit
8
%Purge InProgress
9
Purge Permit
%Start Purge PB
Purge_Request
10
Purge Request
%Start_Purge
11
%Purge_InProgress
12
6.0
13
Purge Delay
Purge_Delay
TON
%Purge_Complete
14
%MFT
Clear MFT Permit
15
%Purge Complete
Clear_MFT_Permit
16
Reset MFT
17
Clear MFT Permit
%Reset MFT PB
Reset_MFT
18
Spark_Delay
0.16667
19
TOF
Reset MFT
Ign Start Delay
%Start Ignitr PB
Start_Ign_Spark
20
Igniter Proven
Igniter_Delay
0.16667
21
TON
Spark Delay
Start Ign Spark
Igniter Delay
%Opn_Ig_Gas_Vlvs
22
%Burner Flame
23
Ig_Proven_Delay
0.16667
TON
Ig_Proven_Delay
Igniter_Proven
24
Igniter Proven
25
Start_Delay
1.0
Start_Delay
TON
Ign_Start_Delay
26
September 2005
15
LADDER LOGIC DESIGN EXAMPLE
CGiLL-1
Ladder to function block conversion for the previous ladder diagram:
AND01.O1
%FDF_Start
DID01.O1
%FDF_Stop_PB
A
AND01.O1
OR01
B
DID01.O0
%FDF_Start_PB
O1
A
A
NOT02
Rung 02
O1 A
B
AND02
B
DID01.O6
%Oil_HdrPress_Lo
A
NOT04
NOT05
DID01.O4
%Drum_Lvl_LoLo
O1 A
DID01.O2
%FD_Fan_Running
AND04
B
NOT03
AND01
O1
B
DID01.O7
%Atom_Med_Hi
A
NOT06
Rung 03
O1 A
O1
O1 A
O1
A
AND03
O1
Boiler_OK
Rung 04
O1 A
B
O1
AND05
O1
Oil_OK
DID01.O9
%Gas_Press_Hi
DID01.O8
%Gas_Press_Lo
AND05.O1
Oil_OK
AND03.O1
Boiler_OK
A
DID01.OB
%Gas_V2_Closed
DID01.OA
%Gas_V1_Closed
NOT01
%FDF_Start
DID01.O3
%Air_Flow_ LoLo
A
DID01.O5
%Oil_Temp_ Lo
Rung 01
B
A
DID01.OC
%Oil_V1_Closed
O1
NOT07
B
NOT08
AND07
AND10
O1
O1
A
DID01.OD
%Oil_V2_Closed
O1
Rung 06
AND08
O1
Op_Requirements
Rung 07
B
AND11
B
AND12
O1
Purge_Precond
Rung 08
A
O1
Purge_Permit
A
OR02.O1
Purge_InProgress
B
AND12.O1
Purge_Permit
AND13
A
B
AND06
A
B
AND08.O1
Op_Requirements
AND12.O1
Purge_Permit
B
O1
Gas_OK
AND11.O1
Purge_Precond
DID01.OE
%Start_Purge_PB
Rung 05
O1 A
AND06.O1
Gas_OK
A
B
AND09
A
A
AND13.O1
AND14
Rung 09
O1
O1
Rung 10
A
B
OR02
O1
Purge_Request
Rung 11
OR02.O1
%Start_Purge
Rung 12
OR02.O1
%Purge_InProgress
Rung 13
OR02.O1
P
DYT01
O1
Purge_Delay
TYPE = ON
PU LAST = NO
DYT TIME = 6.0
DYT01.O1
Purge_Delay
OR02.O1
Rung 14
A
B
AND15
O1
%Purge_Complete
16
September 2005
CGiLL-1
LADDER LOGIC DESIGN EXAMPLES
A
OR03.O1
Clear_MFT_Permit
OR13.O1
%MFT
A
Rung 15
O1
Rung 16
A
AND16.01
AND15.O1
%Purge_Complete
O1
OR03
B
Clear_MFT_Permit
A
OR02.O1
Reset_MFT
OR03.O1
Clear_MFT_Permit
AND16
B
NOT09
B
DID01.OF
%Reset_MFT_PB
OR03.O1
Clear_MFT_Permit
AND17
Rung 17
O1
A
AND17.O1
AND14 O1
B
Rung 18
A
O1
OR02
B
Reset_MFT
Rung 19
P
AND15.O1
DYT02
O1
Spark_Delay
TYPE = OF
PU LAST = NO
DYT TIME = 0.16667
AND22.O1
Ign_Start_Delay
A
NOT10
O1 A
Rung 20
A
DID02.O0
AND15 O1 %Start Ignitr_PB
B
B
OR02.O1
Reset_MFT
AND16
B
O1
C
OR04.O1
AND21.O1
Igniter_Proven
AND15.O1
A
B
Start_Ign_Spark
Rung 21
AND17
O1
AND19.O1
DYT02.O1
Spark_Delay
O1
A
B
AND15.O1
OR03
OR03.O1
B
OR04
C
B
DYT03
O1
Igniter_Delay
O1
TYPE = ON
PU LAST = NO
DYT TIME = 0.16667
DYT03.O1
Igniter_Delay
OR03.O1 A
AND18 O1
P
AND19
O1
B
OR03.O1
Rung 22
A
AND20
O1
%Opn_Ig_Gas_Vlvs
DID02.O1
%Burner_Flame
OR03.O1
Rung 23
A
B
O1
P
AND21
DYT04
O1
Ig_Proven_Delay
TYPE = ON
PU LAST = NO
DYT TIME = 0.16667
DYT04.O1
Ig_Proven_Delay
AND21.O1
AND22.O1
Igniter Flame Proven
A
NOT11
Rung 24
A
B
AND22
O1
Igniter_Proven
Rung 25
O1
P
DYT05
O1
Start_Delay
TYPE = ON
PU LAST = NO
DYT TIME = 1.0
DYT05.O1
Start_Delay
NOT11.O1
September 2005
Rung 26
A
B
AND23
O1
Ign_Start_Delay
17
LADDER LOGIC DESIGN EXAMPLE
CGiLL-1
The graphical configuration of the second secondary page:
Oil_On
27
Reset_MFT
Oil_OK
%Start_Oil_PB
Start_Oil
28
Oil_On
29
Start_Oil
Igniter_Proven
%Stop_Oil_PB
%Open_Oil_Valves
30
Oil_Delay
0.16667
31
TON
%Oil_V1_NotOpen
32
Oil_Delay
%Oil_V2_NotOpen
Oil_Start_Abort
33
%Open_Oil_Valves
Oil_Start_Abort
Oil_On
34
%RecrPmp_Stop_PB
%Close_Recirc
35
%Close_Recirc
%RecrPmp_Srt_PB
36
Gas_Start_Abort
37
Reset_MFT
Gas_OK
Start_Gas
%Start_Gas_PB
38
Gas_On
39
Start_Gas
Igniter_Proven
%Open_Gas_Valves
%Stop_Gas_PB
40
Gas_Delay
0.03333
TON
41
%Gas_V1_NotOpen
42
Gas_Delay
%Gas_V2_NotOpen
Gas_Start_Abort
43
%Vent_NotClosed
44
%Open_Gas_Valves
Gas_Start_Abort
%Burner_Flame
Gas_On
45
Op_Requirements
46
ULC_Loop_Error
47
%Master_Abort_PB
%MFT
48
ULC_Loop_Error
%System_Alarm
49
18
September 2005
CGiLL-1
LADDER LOGIC DESIGN EXAMPLES
Ladder to function block conversion for previous ladder diagram:
OR02.O1
Reset_MFT
A
B
A
DID02.O2
AND25 O1%Start_Oil_PBB
AND22.O1
Igniter_Proven
AND27.O1
AND28 O1
OR05.O1
Start_Oil
B
B
Start_Oil
Rung 29
AND27
O1
DID02.O3 A NOT12 O1
%Stop_Oil_PB
OR06
O1
OR05
A
A
B
Rung 28
A
AND23.O1
A
B
O1
AND26 O1
AND33.O1
Oil_On
OR05.O1
Start_Oil
AND24
B
AND25.O1
AND05.O1
Oil_OK
Rung 27
A
AND33.O1
Oil_On
Rung 30
A
O1
B
AND29
O1
%Open_Oil_Valve
P
AND29.O1
DYT06
Rung 31
O1
Oil_Delay
TYPE = ON
PU LAST = NO
DYT TIME = 0.03333
DID02.O4
%Oil_V1_NotOpen
A
B
AND31.O1
AND30
Rung 32
O1
Rung 33
DYT06.O1
Oil_Delay
A
B
AND29.O1
DID02.O5
AND31 O1 %Oil_V2_NotOpen
A
AND32 O1
B
OR07.O1
Oil_Start_Abort
A
AND30.O1
B
A
NOT13
B
B
NOT14
OR11.O1
Gas_Start_Abort
B
OR02.O1
Reset_MFT
AND36
O1
B
DID02.O8
%Start_Gas_PB
OR09.O1
Start_GAs
AND22.O1
Igniter_Proven
AND34
OR09.O1
Start_Gas
September 2005
AND38.O1
AND39 O1
A
B
AND33
Oil_On
Rung 35
O1
B
OR10
Rung 36
A
B
OR08
O1
%Close_Recirc
Rung 37
AND35
O1
Rung 38
A
AND37 O1
AND35.O1
A
B
OR09
O1
Start_Gas
A
AND46.O1
Gas_On
A
B
Rung 34
O1
A
AND36.O1
A
Oil_Start_Abort
A
A
AND34.O1
DID02.O7
%RecircPmp_Strt_PB
AND06.O1
Gas_OK
OR07
O1 A
AND29.O1
%Open_Oil_Valves
OR08.O1
%Close_Recirc.
DID02.O6
%RecircPmp_Stop_PB
O1
B
AND38
DID02.O9 A NOT15 O1
%Stop_Gas_ PB
O1
Rung 39
O1
Rung 40
A
B
AND40
O1
%Open_Gas_Valves
19
LADDER LOGIC DESIGN EXAMPLE
CGiLL-1
P
AND40.O1
DYT07
O1
Gas_Delay
TYPE = ON
PU LAST = NO
DYT TIME = 0.03333
DID02.OA
%Gas_V1_NotOpen
DYT07.O1
Gas_Delay
AND40.O1
A
B
AND42
Rung 42
A
AND41
B
AND42.O1
DID02.OB
%Gas_V2_NotOpen
O1
O1
Rung 43
A
B
AND43
AND41.O1
O1
DID02.OC
%Vent_NotClosed
AND40.01
%Open_Gas_Valves
NOT16
Gas_Start_Abort
O1
DID02.O1
%Burner_Flame
AND45
OR11
c
Rung 44
AND44
B
O1 A
B
O1
A
AND42.O1
A
A
B
AND44.O1
OR11.O1
Gas_Start_Abort
O1
Rung 45
A
B
AND46
O1
Gas_On
AND08.O1
Op_Requirements
ODS.LE
ULC_Loop_Error
Rung 41
AND08.O1
Rung 46
A
B
OR12
DID02.0D
Master Abort PB
Rung 47
O1
OR12.O1
Rung 48
A
B
OR13
O1
%MFT
Rung 49
ODS.LE
ULC_Loop_Error
%System_Alarm
„
20
September 2005